1. Field of the Invention
The present invention relates to a digital camera system connecting plural units of digital cameras and letting the camera collaborate to work.
2. Description of Related Art
In this field of the art, there are the needs for making a hard copy of an image taken by a digital camera with a page printer directly, not through a personal computer, various systems have been introduced from many companies and some of them have been actually marketed as a commercial product. On top of that, as an interface standard, for example, in the field of USB (Universal Serial Bus) standard, USB On-The-Go standard that enables even a mobile apparatus only with simple functions to act as a host with a decreased load of a master but not using a large apparatus like personal computer and the like has been released as a additional standard to USB2.0. With this standard, even a mobile apparatus can be a host and also each role of a host and a peripheral apparatus can be replaced at any time when required.
As other standards sending/receiving a data to and from apparatus, various standards like Bluetooth standard, wireless LAN (IEEE802.11 and others), IEEE1394, IrDA (Infrared Data Association) and IrBurst (IrDA for a next generation version) have been proposed. With improvement of the data transfer infrastructure in this way, it is obvious that a data exchange between compact apparatus such as a digital camera, a printer, a PDA, a mobile cellular phone and a hard disk drive compatible with USB will be made more frequently regardless of makers and product models.
And, many companies have put a variety of digital cameras on the marketplace with a short product cycle, so a going price of a digital camera marketed just while ago goes down drastically and getting a camera becomes easy. Under this market situation, there are not few households that have plural digital cameras. Accordingly, a market environment enabling a consumer to have or easily obtain plural cameras becomes available for a consumer and then there are the needs that a consumer wants to try a new way of usage that has been impossible with a single camera by using several cameras.
Japanese Patent application (hereinafter referred to as JPA) 8-84282 introduces a system in which a master camera sends to a slave camera an operation data like a zooming and a focusing and the slave camera takes a shot and then sends a compressed image to the master camera where the taken compressed image is checked. JPA 9-284696 discloses a system in which connected electric cameras via a communication device lets a camera with a specific key being pressed act as a master camera and the master camera takes a picture, erase an image data of the salve camera through an operation of a slave camera and monitors an image of a slave camera. JPA 2000-113166 proposes a server for controlling a camera in order to cause several cameras to connect to work via a network.
In JPA 2000-134527 where a digital camera is connected to each other and one digital camera operates other digital camera, a reproduced image of a slave camera is transferred to a master camera with a frame number simultaneously and displayed. JPA2001-8089 proposes a system in which shooting information about a shutter speed, an aperture value, an exposure compensation value and so is transferred to a slave camera and a picture is taken based upon this information. Japan Patent Applications 2001-111866 and 2001-169173 propose a system in which a common image is taken connecting plural digital cameras with different functions. JPA2001-166374 proposes a trigger system in which each camera can take a higher speed shot than a burst shot is taken by each camera, controlling plural cameras. USP2002/0118958 discloses a video camera system in which a parent device and a child device take a picture in response to a synchronization signal sent from the parent device and this data is sent/received. JPA2002-101226 discloses an imaging device that changes a capacity of an image to be sent/received corresponding to a data transfer capacity.
The foregoing various standards define a data transfer method, but not a working role of each camera in connecting plural digital cameras. Although a digital camera loaded with Bluetooth is available now in the marketplace, its function is quite simple to transfer a data between cameras and instruct to release a shutter from other camera.
It is an object of this invention to provide a digital camera and a digital camera system having a new function that will be realized for the first time when letting plural cameras collaborate to work.